1. Field of the Invention
The present invention relates to wireless communication, and in particular, relates to a technology suitable for setting wireless communication at the time of installation.
2. Description of the Related Art
Conventionally, digital X-ray imaging apparatuses have been commercialized. The digital X-ray imaging apparatus generates X-rays to acquire X-ray image data from an X-ray sensor, performs analog-to-digital (A/D) conversion on the X-ray image data into digital X-ray image data, and performs image processing on the digital X-ray image data for diagnosis. An arrangement of a conventional X-ray imaging apparatus is illustrated in FIG. 3, for example. As illustrated in FIG. 3, in the conventional digital X-ray imaging apparatus, an X-ray sensor 1001 is generally installed on an upright stand or a table and is tethered with a cable to be used.
However, depending on an image capture method, it is necessary to capture X-ray images at a free position without fixing the X-ray sensor. In response to such a necessity a portable X-ray sensor has been proposed. For example, Japanese Patent Application Laid-Open No. 2003-172783 discusses an X-ray imaging apparatus including a thin and lightweight type X-ray sensor which is easy to handle. Japanese Patent Application Laid-Open No. 7-140255 discusses an X-ray imaging apparatus in which an X-ray sensor and a synchronous repeater are wirelessly connected to eliminate installation limitations of an X-ray sensor 1101 due to a cable, as illustrated in FIG. 4.
To provide a high-quality X-ray image, the pixel pitch of the X-ray sensor is about 100 to 200 μm and a 16-bit density resolution is used. If an image region size is 17″*14″ (43*35 cm), the data size constituting one image becomes generally 7.5 to 30 megabytes. To display an X-ray image at a speed of several seconds on a display after capturing the X-ray image at a free position and acquiring X-ray image data of the above size, a wireless communication unit is also required to be correspondingly fast. To easily realize such a high speed performance, a radio frequency (RF) wave is used for wireless communication.
Regarding RF waves, however, local RF regulations differ according to countries and regions, and available frequency bands are regulated for each country or region. Thus, individual and specific RF wave setting is required for an X-ray imaging apparatus according to the country or the region. Therefore, the RF wave setting has conventionally been performed on the apparatus according to a destination or an installation site at the time of shipment or the installation by human work.
However, the radio frequency (RF) wave settings established by human work are prone to the occurrence of operational error. If an operational error occurs and RF wave communications is set to a band out of regulation, the X-ray sensor may fail to operate properly and/or it may operate outside of regulated conditions which may be against local or regional laws.